4. ACORN
(Nicholas Kamm/AFP/Getty Images)
Members of the Association of Community Organizations for Reform Now (ACORN) hold banners before disrupting a public auction of a foreclosed home in Washington, D.C.
Undercover video of ACORN workers advising conservative activists posing as a prostitute and her pimp on criminal activities, including tax evasion and human trafficking. An internal ACORN probe found no wrongdoing.
